Monorail vehicle switching arrangement

ABSTRACT

A monorail vehicle switching arrangement comprises a guidewaymounted movable ramp for actuating a guidance system on a vehicle to shift the guidance system from one operating mode to another operating mode to steer the vehicle from one section of the guideway through a switch and to a second section of the guideway. The guidance system includes guide wheels that engage upper and lower guide blades on the guideway for effecting the vehicle heading. The ramp is a bistable member which can be positioned up for effecting switching of the vehicle to the second section and positioned down to allow the vehicle to proceed on the first section. A switch machine is mounted on each side of the guideway for operating a ramp and locking it either up or down on each side of the guideway.

United States Patent 1 1 Wright et a1.

[ Aug. 20, 1974 MONORAIL VEHICLE SWITCHING ARRANGEMENT Inventors: Raymond W. Wright; Robert W.

Corey, both of Dallas, Tex.

Assignee: Monocab Inc., Garland, Tex.

Filed: Nov. 29, 1972 Appl. No.: 310,430

US. Cl 104/105, 104/130, 104/88, 105/215 R Int. Cl E0lb 25/22 Field of Search 105/215; 104/88, 130, 105, 104/96 References Cited UNITED STATES PATENTS Alimanestianu 104/88 Marty 104/30 Holt 104/130 Desilets... 104/88 Primary ExaminerM. Henson Wood, Jr. Assistant Examiner-D. W. Keen Attorney, Agent, or Firm-Olson, Trexler, Wolters, Bushnell & Fosse, Ltd.

[57] I ABSTRACT A monorail vehicle switching arrangement comprises a guideway-mounted movable ramp for actuating a guidance system on a vehicle to shift the guidance system from one operating mode to another operating mode to steer the vehicle from one section of the guideway through a switch and to a second section of the guideway. The guidance system includes guide wheel s tliat engage 'E'ppe'r and lowerg uide blades on the guideway for effecting the vehicle heading. The ramp is a bistable member which can be positioned up for effecting switching of the vehicle to the second section and positioned down to allow the vehicle to proceed on the first section. A switch machine is mounted on each side of the guideway for operating a ramp and locking it either up or down on each side of the guideway.

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PAIENIEBAuszman sum in nr 14 MONORAIL VEHICLE SWITCHING ARRANGEMENT BACKGROUND OF THE INVENTION This invention relates to improvements in switching arrangements for monorail transportation systems.

In the operation of transportation systems of the overhead monorail guideway type, it is necessary to provide a switching arrangements for switching vehicles along predetermined guideway sections in accordance with the desired vehicle destination. Typically, for example, the guideway may include a mainline section and a siding to which the vehicle is diverted when it is desired to have the vehicle stop at a station on the siding. The guideway must, therefore, embody a switch that coacts with the vehicle to establish the correct vehicle heading.

In one known form of monorail transportation systems, the vehicle comprises a cab that is suspended from a propulsion system. The primary portion of the propulsion system supports the weight of the cab, and guidance mechanisms carried by the vehicle cooperate with the guideway to determine the heading of the vehicle. All movable parts of the vehicle involved in route selection are on-board the vehicle, and the guideway elements that cooperate with the on-board guidance are static OBJECTS AND SUMMARY OF THE INVENTION It is an object of the present invention to provide a monorail vehicle switching arrangement that utilizes an on-board guidance mechanism which is actuated by a switching ramp on the guideway such that the guidance mechanism is positioned in a mode to cause movement of the vehicle along a predetermined route, for example, diversion of the vehicle from the mainline to a branch line.

It is a further object of the present invention to provide a switching arrangement of the type stated in which the guidance system on the vehicle is part of a bogie from which the passenger cab is suspended, and wherein the guidance system is not relied upon to support the overall weight of the vehicle.

It is another object of the present invention to provide a switching arrangement of the type stated in which the guidance system is shiftable to and from either of two modes for cooperation with upper and lower guide blades on the guideway for establishing the path of travel of the vehicle.

It is a still further object of the present invention to provide an arrangement of the type stated in which the movable switching ramp is pivotally mounted on the guideway and is operated by a novel switch machine that may be remotely controlled for bistable positioning (i.e., up or down) to effect actuation or nonactuation of the vehicle guidance system as the bogie travels past the ramp.

It is a still further object of the present invention to provide a switching arrangement which is relatively simple and has a high degree of safety.

In accordance with the foregoing objects the present invention includes a first guideway section and a second guideway section diverging from the first guideway section and cooperating therewith to define a switch. A first guide blade is provided on the first guideway section and a second guide blade is provided on the, second guideway section and which diverges from the first guide blade. A bogie has wheels for rollable support on spaced apart running surfaces on the guideway. The bogie includes opposed guide wheels pantographically connecting the guide wheels together for shifting between two modes. The guide wheels are on opposite sides of the first mentioned guide blade in either mode when the bogie is in the first-mentioned guideway section and approaching the second guideway section. The guide blades have opposed surface portions engaged by the guide wheels and so shaped that one mode of the guide wheels will cause movement of the bogie through the switch and continue in the first guideway section and the other mode of the guide wheels will cause movement of the bogie through the switch and on to the second guideway section. The bogie has cooperating means for engagement with a movable ramp on the guideway for shifting the guide wheels from one of the two modes to the other mode.

A switch machine for operating a guideway ramp comprises a switch motor that includes a power driven shaft, a driven structure including a ramp arm for lifting the ramp from its non-operating position to its switchoperating position, a first means for driving the driven structure from the power driven shaft, locking means responsive to the position of the driven structure and cooperating therewith for automatically locking the ramp in its switch-operating position when that position has been reached, and second means for unlocking the locking means to permit the ramp to drop downwardly to its non-operating position. Furthermore, the ramp is in an electric circuit when in the switch-operating position or in the non-operating position so that the position of the ramp can be electrically detected at a control center for the system. There are two such machines for each guideway switch intersection.

BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a perspective view of a portion of a monorail transportation system embodying the present invention;

FIG. 2 is a diagrammatic plan view of one type of system layout embodying the invention;

FIG. 3 is a sectional view, partially structural and partially diagrammatic, taken through a switch region of the system, in the present case being along line 3-3 of FIG. 2;

FIG. 4 is a fragmentary sectional view, also partially structural and partially diagrammatic, and taken along line 4-4 of FIG. 2; a

FIG. 5 is a fragmentary top plan view, partially structural and partially diagrammatic, of a switch portion of the guideway; I

FIGS. 6 and 7 are fragmentary sectional views taken along lines 6-6 and 7-7, respectively, of FIG. 5;

FIG. 8 is a perspective view of a vehicle bogie that forms part of the present invention configured for right-hand guidance;

FIG. 9 is a sectional view transversely of the guideway as seen approximately along line 9--9 of FIG. 5 and showing a vehicle at that region plus pertinent structural details of the bogie and of the the normal direction of travel;

FIGS. 10 and 11 are fragmentary sectional views on an enlarged scale, taken along lines 10-10 and ll--ll, respectively, of FIG. 9;

guideway in FIG. '12 is an enlarged fragmentary elevational view, partially in section, of a portion of FIG. 9;

FIG. 13 is a fragmentary top plan view, partially broken away and in section, of the structure of FIG. 12;

FIG. 14 is a top plan view of a switch machine that forms part of the present invention;

FIG. 15 is a fragmentary sectional view taken along line 15-15 of FIG. 14;

FIG. 16 is a perspective view, partially diagrammatic and partially structural, of mechanism in the switch machine;

FIG. 17 is a fragmentary sectional view taken along line 17-,l7 of FIG. 15and showing the switching ramp in the down position;

FIG. 18 is a view similar'to FIG. 17 but showing the switching ramp in its elevated or up position;

FIG. 19 is a fragmentary sectional view taken along line l919 of FIG. 17;

FIG. 20 is a fragmentary elevational view as seen approximately from line 20-20 of FIG. 19;

FIG. 21 is a circuit schematic for the switch machine; and

FIG. 22 is a section similar to FIG. 9 but showing the vehicle in the right-hand guidance mode.

DETAILED DESCRIPTION Referring now in more detail to FIG. 1 of the drawing, there isshown a transportation system that comprises, an overhead monorail guideway 2 that is suspended from a series of columns or posts 4 to define a guideway layout in accordance with the areas to be serviced by the system. The invention herein described is not limited to any particular kind of guideway layout. However, one layout which may serve to illustrate the principles of the invention is shown in FIG. 2. The layout therein comprises a mainline section 6, which is an endless loop, and a siding 8. When viewed in the normal direction of travel indicated by arrow 10 the siding or second guideway section 8 diverges from the first or mainline section 6 and cooperates therewith to define a switch 12. The siding 8 leads to a station 14 and again merges at a switch 16 with the mainline section 6. The system of FIG. 2 may also include a spur 18 that leads to an auxiliary station 20, which may be a maintenance area. Thus, in the normal course of things a vehicle 22 can travel clockwise around the mainline section 6, bypassing the station 14, or the vehicle may be guided into siding 8 and to the station 14. Also, a vehicle may be positioned on the mainline section 6 at a region 24 and then backed through a switch 25 on to the spur l8 and into the maintenance area 20.

As best seen in FIG. 9 wherein the guideway is shown in cross section, the latter may be made up of I-beam side members 26, 26 and a series of tubular top members 28, 28, 28 which define a generally rectilinear configuration and from which the vehicle 22 is suspended. Referring to FIGS. 2-5 in conjunction with FIG. 9, the guideway 2 also includes an upper guide blade 30 which is centrally between the side members 26 and depends from the center top member 28. At its lower margin the guideway is provided with angle members which form running surfaces 32, 32 and which are spaced apart to leave an opening 34 therebetween, all

for purposes presently more fully appearing. Secured to and depending from the left-hand (FIG. 9) running surface 32 is a lower guide blade 36 which is laterally offset but parallel to the upper guide blade 30. In the system herein illustrated, and as will best be seen from FIG. 2, the lower guide blade 36 is at the left-hand side of the guideway, viewed in cross section and in the normal direction of travel indicated by the arrow 10. For purposes which will become apparent hereinafter, there is an additional lower guide blade 38 that extends over the mainline section that runs between the switch ing areas l2, 16. In addition, there is an additional lower guide blade 40 which extends from a point somewhat to the left (FIG. 2) of switch 25 along the spur l8 and to the maintenance station 20.

It will also be seen from FIG. 5 that at the switch 12 the upper guide blade 30a for the siding 8 diverges from the upper guide blade 30. However, the upper guide blade 30a remains centered within the siding 8-. Furthermore, the running surfaces 32a, 32a of the siding 8 will provide a different vehicle heading from the running surfaces 32, 32 of the mainline section 6. In the region of the switch 12 there will be a gap in the running surfaces. If the vehicle 22 is to continue along the mainline section 6, the right-hand (FIG. 3; also FIG. 5 viewed in the direction of arrow 10) running surface 32 will be continuous but the left-hand running surface 32 will have a gap. This results from the left-hand running surface 32 merging at an angle with running surface 32a and continuing into the siding 8. The gap in the lefthand running surface will not be picked up again in the mainline section until past the switch 12. Similarly, if the vehicle is to be diverted into the siding 8, the lefthand running surface 32 will be continuous. The opposite or right running surface will have a gap which will not end until past the switch 12.

Referring now more particularly to FIGS. 8-13, the vehicle includes a bogie 42 from which a passenger cab 44 is suitably suspended. The bogie. 42 has a main frame that includes a central frame section 46 with upper beams 48, 48 and a lower beam 50. At the opposite ends of the central frame section are uprights 52, 52 which are of like construction and whose lower ends have flanged hubs 53, 53 and through which the passenger cab 44 may be suitably connected to the bogie. It may be noted that the cam 42 may include a resilient suspension arrangement that connects to the hub 53, such suspension system being of any conventional type. The uprights 52, 52 may include ears 54 (one being shown in FIG. 8), for respectively receivirig pivot pins 56 and 'by which forward and rearward frame extensions 58, 58 may be pivotally connected to the central frame section for movement about vertical axes. The frame extensions 58, 58 each journal a pair of running wheels 60, 62 that are adapted for rollable disposition on the running surfaces 30, 30a, .32, 32a, as the case may be. The lower portions of the uprights 52, 52 will, as seen in FIG. 9, project through the opening 34 between the facing edges of the running surfaces 32, 32. The normally forward pair of running wheels 60,62 at the left of FIG. 8 are power driven in a conventional manner through an electric motor 64 that is between the upper and lower beams 48, 50. Also disposed between the upper and lower beams 48, 50 is an air compressor 66 for supplying compressed air to the braking system of the vehicle, door machanism, and the likein a known manner. Power may be supplied to the motor and compressor from conventional guideway conductor arrangements 67. Collector arrangements of known type are mounted on each side of the forward uprights 52.

The pivotal connections of the front and rear extensions 58, 58 through the pivot pins 56 permit the front and rear pair of running wheels to swivel relative to the central portion of the bogie 42. Thus, the bogie 42 is readily able to traverse curves in a guideway of much shorter radius of curvature than would ordinarily be possible without the aforesaid pivotal connections. F urthermore, the drive wheel 60, 62 are preferably of the pneumatic type, which enhances the ability to negotiate curves on the guideway as well as providing improved riding qualities for the vehicle.

A pair of pantographically connected upper guide wheels 68, 70 is mounted on each frame extension 58. A like pair of pantographically connected upper guide wheels 68a, 70a is mounted on each upright 52 at the upper end thereof. As seen in FIG. 8, the guide wheels 68a, 70a are rotatable about the axes of pins 72, 74 which are vertically disposed and are joined to guide wheel brackets 76, 78. The guide wheel brackets 76, 78 are joined by parallelogram or pantograph links 80, 82 which are each pivotally connected at their respective opposite ends to each of the brackets 76, 78. The center of each link 80, 82 is pivotally connected to the upper end portion of the associated upright 52.

Parallel connecting rods 84, 86 are pivotally connected respectively at their upper ends to the lower link 82 on opposite sides of the pivot connection of the link 82 to the upright 52. The rods 84, 86 project downwardly for respective pivotal connections to the upper link 88 of a lower pantograph comprised of a link 88 and a link 90. The links 88, 90 are pivotally connected centrally of each to the lower end of the upright 52 and are, in addition, pivotally connected to lower guide wheel brackets 92, 94. The lower guide wheel brackets 92, 94 support lower guide wheels 96, 98 which are rotatable about vertical axes just as are the upper guide wheels. By reason of the foregoing pantographic connections, the guide wheels 68a, 70a, 96, 98 will move in unison from one guidance mode to another guidance mode for purposes presently to be described. Additional lower guide wheels 100, 102 are supported at the lower ends of the respective uprights 52, 52. These lower guide wheels 100, 102, while supported for rotation about parallel axes, are not connected to the aforesaid pantograph and so the lower guide wheels 100, 102 do not change their relative height with respect to the bogie.

The upper guide wheels 68, 70 which are on the extensions 58, 58, are constructed and arranged similar to the guide wheels 68a, 70a, previously described. However, there are no lower guide wheels associated with the upper guide wheels 68,70 as none are necessary in the present invention. FIGS. -13 show detailed features of one pair of upper guide wheels 68a, 700, it being understood that there is a like mechanism associated with the other set of guide wheels 68a, 70a. Except for the absence of lower guide wheels and connecting rods, the upper guide-wheels 68, 70 and guidance shifting structureare the same as that for the guide wheels 68a, 70a. Furthermore, corresponding parts which have been previously described with respect to the guide wheels 68a, 70a are also applicable to the detailed structure shown in FIGS. 10-13 and corresponding reference numerals show corresponding parts with respect to the arrangement shown in FIGS. 8, 9 and 22.

FIGS. l0-13 show an arrangement by which the upper guide wheels may be unlocked when in one operating mode, then shifted to the opposite operating mode, and then locked in that mode. However, before describing this aspect of the invention the manner in which the guide wheels cooperate with the guide blades on the guideway will be described.

The upper guide wheels 68, 70 and 68a, 70a engage opposite vertical surfaces of the upper guide blade 30. Similarly, lower guide wheels 96, 102 engage the opposite vertical surfaces of the lower guide blade 36. Where the guideway contains the lower guide blade 38 the lower guide wheels 98, 100 will engage the opposite vertical surfaces thereof when in the up position. The guidance may be left-hand or right-hand depending upon the system layout, the normal direction and path of travel of the vehicle, and whether or not the vehicle is to be switched to a siding or spur. As the terms are used herein, the hand of guidance is determined by viewing the vehicle in the direction of travel and noting whether or not the lower guide blade is at the left or 'right side of the guideway. FIGS. 4 and 9 show lefthand guidance, it being understood that the lower guide blade 38 in FIG. 9 is not in the plane of the section 99 and is not, when the vehicle is at 99, engaged by the guide wheels 98, 100. With reference to FIG. 2, it will be noted that the system is designed for normal left-hand guidance as this type of guidance is present in the station siding 8 and in the mainline loop running clockwise from the switch 16 to the switch 12. Right-hand guidance is found in the portion of the mainline section 6 at which the lower guide blade 38 is located, namely running clockwise or to the right (FIG.

' 2) from the switch 12 to the switch 16. Two lower guide blades 36, 38 and two upper guide blades 30, 30a are shown in FIG. 3 as this would be the guidance configuration in the region of a crossover or switch. Righthand guidance would be present for a vehicle coming out of the maintenance station 20.

It will thus be seen that left-hand guidance is required for a vehicle traversing the mainline section of the guideway and entering the station siding 8. Right-hand guidance is utilized when the station 14 is to be bypassed.

When the guide wheels are in the left-hand guidance mode the guide wheels 70,-a are higher than the guide wheels 68, 68a. The left-hand lower guide wheels 96, 102 are at the same level. In right-hand guidance the guide wheels 68, 68a are above the guide wheels 70, 70a and the lower guide wheels 98, will be at the same level. The arrangement of the upper and lower guide wheels in either mode and their cooperation with the upper and lower guide blades of the guideway imparts stability and anti-sway characteristics to the vehicle.

In order to establish the proper guidance mode the system includes a number of static switching ramps 19, 104a-104f and a number of dynamic or movable switching ramps l06a-106d all of which are mounted.

on the guideway. The movable switching ramps 106a 106d are pivotally mounted on the guideway, and each is operated by a switch motor 108. The switch motor and ramp 106a are shown in FIGS. 14-21 and will hereafter be described in greater detail. Suflice it to say for the present, however, that in a typical operation the vehicle will be approaching the ramps 106a, l06b with left-hand guidance and will either be diverted along the siding 8 to the station 14 or will bypass the station 14 and continue along the mainline guideway section 6. If the ramp 1061: is up left-hand guidance will be maintained and the vehicle will be diverted onto the siding 8, because the rollers 124 make contact with the ramp 106a and maintain wheels 70, 70a in the raised position. The ramp 106a must be, as a safety feature, in the down position and is so down in FIG. 2.

When the vehicle is diverted onto the siding 8 it is necessary that the upper guide wheels 68, 68a pass across or clear the upper guide blade 30. Similarly, it is necessary that the lower guide wheel 98 clear the lower guide blade 38 at the switch or crossover 12. Referring to FIGS. 2-7 it will be seen that the upper guide blades 30, 30a are cut away to provide clearance areas 110 (FIG. 6), which reduces the height of the upper guide blades in the region of the switch 12. Similarly, and as shown by FIG. 7, the lower guide blade 38 (and guide blade 36 as well) are cut away to provide clearance areas 112, thereby reducing the height of the guide blades thereat. These clearance areas 110, 112 allow the right-hand upper and lower guide wheels to move under and clear the respective upper. and lower guide blades during switching. Thus, with diversion of the vehicle onto the siding 8 the upper guide wheels 68, 68a will clear the upper guide blade 30 and the lower guide wheels 98 will clear the lower guide blade 38. Similarly if the switch ramp 106a is up (and ramp l06b is down) to establish right-hand guidance to cause the vehicle to continue in the mainline loop 6, the upper guide wheels 70, 70 a will clear the upper guide blades 30a and the lower guide wheels 96 will clear the lower guide blade 36.

From the foregoing it will be apparent that with lefthand guidance and upon reaching the switch area, the upper guide wheels 70, 70a continue to engage the lefthand side of the upper guide blade 300 (see FIG. 3) but the opposite upper guide wheels 68, 68a are free of contact from an upper guide blade due to the reduced guide blade height and the lower level of the guide wheels 68, 680. This condition remains until the switch area is substantially passed and the upper guide blade 30a is again at its full height for engagement with both of the upper guide wheels 68, 68a. The lower guide wheels 96, 102 are maintained in engagement with the opposite sides of the lower guide blade 36 (FIG. 3) during switching with left-hand guidance. An auxiliary upper guide blade 114 is provided in the crossover or switching region to assist in imparting lateral stability to the upper guide wheels 70, 70a. A like guide 114a is also provided oppositely thereto.

Right-hand guidance is actuatedby rollers 124a making contact with ramp 106a which itself has been actuated by the switch machine 108 to the up position (ramp l06b having been actuated to the down position). With right-hand guidance the upper guide wheels 68, 68a will engage the right-hand side of the upper guide blade 30 through the. switch area and the upper guide wheels 70, 70a will be free of contact of the upper guide blade 30 in the cut away region 110. The guide wheels 70, 70a clear the guide blade 30a and again contact the guide blade 30 at the end of the cut out area 110. Similarly, the lower guide wheels 98, 100, having picked up the right-hand lower guide blade 38 just before the switching area 12, will engage opposite sides thereof through the switching area and continue such engagement until the left-hand guidance is subsequently restored.

Various static ramps 119, 104a-104f are located at suitable points around the system to insure that the guide wheels are in the proper guidance mode for both forward and reverse direction of vehicle travel. The number and the position of such static ramps will, of course, depend upon the system layout. The purpose of such static ramps are to insure or qualify the guidance for safe and proper operation.

Furthermore, each of the upper and lower guide wheels is preferably covered with rubber, plastic or other friction material to insure positive rolling contact with the upper and lower guide blades.

As a further safety feature auxiliary static ramp sections 119 are associated with each movable ramp. For example, auxiliary ramp sections 119 associated with the movable ramps 106a, l06b are respectively in the mainline sections 6 and siding 8 and 18. This eliminates the need for a long movable ramp and acts as a safety lock feature to insure the proper guidance mode at least through the switch region. Further, these ramps have inclined surfaces at their trailing ends which become the lead end inclines when backing to properly position the guidance in the reverse direction of travel.

Referring now to FIGS. 8 and 10-13 it will be seen that each upper guide wheel assembly includes ramp arms 120, 120a, one arm being associated with each bracket 76, 78. The ramp arms 120,1200 are pivotally mounted on their respective brackets by pivot pins 122, 122 which are journaled in bearings 123, 123 (FIG. 13) in the respective brackets 74, 76. Each ramp arm 120, 120a carries a roller 124, 124 that is rotatably mounted on a pivot shaft 126, 126. Between each roller 124 and its associated pivot pin 122 is an additional roller 128 that is journaled in the arm 120, 1200, as the case may be, and has a small segment thereof upwardly projecting from the upper surface of the ramp arm 120, 120a.

The pivot pins 122, 122 are rigidly connected to each associated ramp arm.120, 120a by nuts 130, 130 (FIG. 13) which are threaded onto a reduced end of the pivot pin 122. The nuts 130 also retain locking arms 132, 132a which are keyed to the pins 122, 122 for rotation therewith. Thus locking arms 132, 132a rotate with ramp arm'l20 or 120a, as the case may be. When the guidance is in the left-hand mode, as shown in FIGS. 10-13, the locking arm 132a fits into a downwardly and laterally opening notch 134, FIG. 1 1) in the upright 52 to lock the guide wheels in the left-hand guidance mode. There is a corresponding notch 134 on the other side of the upright 52 for engagement with the locking arm 132 when the guidance is in the right-hand mode. However, since left-hand guidance is shown, the locking am 132 is out of that notch, and is positioned as shown in FIG. 10. It should be noted that with respect to the guide wheels 68, 70, these notches will be in corresponding places on the extensions 58.

Rockably mounted in each bracket 74, 76 above the associated ramp arm 120, 120a is a lifter cam 136 having a shaft portion 138 (FIG. 13) journaled in bearings 140 that are mounted in the respective brackets 74, 76. The end of the shaft portion 138 receives a nut 142 which, along with a key, secures an override arm 144 onto the shaft portion 138. The override on the arm 144 has a nose portion 146 that is loosely pivoted at an elongated hole. 148 to the upper clevis end 150 of an overtravel rod 152. This pivotal connection is through a pivot bolt and nut assembly 154. The overtravel rod 152 projects downwardly through an opening 156 in the upright 52. The lower end of each overtravel rod 152 is threaded for receiving a stop collar 158 that is adapted to slide in the lower flange 160 (FIG. 12) of the brackets 76, 78. As illustrated, stop collar 158 associated with the bracket 76 abuts the upright 52 just below the opening 156 thereof. The stop collar 158 associated with the bracket 78 is downwardly spaced relative to the stop collar 158 associated with the brackets 76 and does not abut the upright 52. However, in the opposite or right-hand guidance mode, the stop collars 158, 158 and their associated overtravel rod 152, 152 will be disposed oppositely from that shown in FIG. 12.

A spring abutment 162 is pivotally attached to the face of each lifter cam 160 for supporting one end of a compression-return spring 164. The other end of the spring 164 abuts a small block 166 that is pivotally mounted on each bracket 76, 78. The abutment 162 includes a rod 168 that slidably projects through the block 166. Spring 164 biases the lifter cam 136 in opposition to force applied thereto by the stop collar 158 acting against the upright 52.

If the guidance mode is to bechanged from left-hand to right-hand, one way for this to occur is to have the movable ramp 106a up and the movable ramp 1061) down and with the vehicle approaching the switch 12 from the left, reference being made to FIG. 2. As the roller 124 of ramp arm 120a rolls along the raised switching ramp 106a, the arm 120a rotates clockwise (FIG-ll) about the axis of pivot pin 122. Upon sufficient rotation of the locking arm 1320 is rotated out from the locking notch 134 whereby the brackets 76, 78 and guide wheels 68a, 70a are now floating." Further movement of the roller 124 up the switching ramp causes further rotation of the ramp arm 120a until the roller 128 thereon engages the lifter cam 136 associated therewith. Further movement of the roller 124 up the switching ramp now causes a vertical movement of the brackets 76 and 78, and hence the guidance wheels 68a and 70a this being the initial movement of the guidance mode change. Further movement of the roller 124 up the switching ramp and associated vertical movement of the brackets 76 and 78 causes the stop collar 158 (FIG. 12), at a discreet pre-set position, to engage against a surface 170 on the upright 52 (FIG. 12). Yet further vertical movement of the brackets 76 and 78, caused by further movement of the roller 124 upon the switching ramp, causes counterclockwise rotation of the lifter cam 136 against the roller 128 due to the overtravel rod being arrested by the action of the stop collar 158 against the surface 170. Continued vertical movement of the brackets 76 and 78 allows the locking arm 132 (FIG. to fall into position in its associated locking notch 134 due to the weight of the ramp arm 120. The guidance assembly is now in the right-hand mode and locked in that condition. At this time, should the brackets 76 and 78 be required to move vertically yet further, the discreet setting of the stop collar 158 will cause a further small amount of rotation of the lifter cam 136 and disengage it from the action of the roller 128. The ramp arm will now be free to rotate independently further-in a redundant manner, the locked guidance configuration being unaffected;

This condition is known as overtravel. Each of the successive sets of guide wheels of the bogie operate in a like manner. In returning to left-hand guidance the roller 124 associated with the ramp arm 120 will engage a switching ramp to withdraw the locking arm 132 from its associated locking notch 134 whereupon the brackets 76, 78 shift their positions in the manner previously described except that the action of the lifter cam, override arm and over-travel rod takes place on those parts associated with the bracket 78.

Referring again to FIG. 5 it will be noted that as the vehicle-moves through the switch 12 either the port running wheels 62, 62 or the starboard running wheels 60, will, for a limited period of time, be off of any of the running surfaces. Typically, FIG. 5 shows the running wheels 60, 62 on running surfaces 32, 32 just before the switch 12. However, in broken lines it is noted that the port wheels 62, 62 are on the running surface 32 of the siding 8 but the starboard wheels 60, 60 are not on any running surface and will not pick up the opposite running surface 32 until further into the siding 8. A like situation occurs with respect to the port running wheels 62, 62 when the vehicle continues through the mainline section 6. This interruption in the running surface results in an increase in deflection of the pneumatic tired wheels, either port or starboard as the case may be. Assuming left-hand guidance and diversion of the vehicle into the siding 8, the port running wheels 62, 62 will deflect and the brackets 76 and 78 will now be required to further move in a vertical direction due to the action of the roller 124 on the auxiliary static ramp 119.(FIG. 2). The descreet setting of the stop collar 158 will cause a further small rotation of the lifter cam and disengage it from the action of the roller 128, the ramp arm now being free to rotate independently further in a redundant manner, the locked guidance condition being unaffected and can only be unlocked by actuation of the opposite ramp arm a. Comparable conditions apply during right-hand guidance through switch 12 as respects overtravel of the arm 120a and its associated lifter cam.

Reference may now be had to FIGS. 14-20 which illustrates a switch machine 108, previously referred to generally herein. However, before describing the switch machine 108 it will be noted that the switching ramp 106b actuated thereby is pivotally mounted on the inside of the guideway by a pivot pin 176. The ramp 106b is driven by a ramp arm 178 that is operated by the switch machine 108. The ramp arm 178 has a roller follower 180 that engages the ramp l06b at a follower guide 182 on the ramp l06b and in which the follower 180 is rollable.

The forward end of the ramp 10612 has a ramp exten-. sion 184 mounted thereon which carries an electrical contact 186. Adjacent to the forward ends of the ramp extension 184 and secured in fixed relation to the guideway as by an angle member is a contact assembly 192. The assembly 192 includes contacts 194, 196 which are electrically insulated from the metal of the guideway. The assembly 192 also has resilient contact blades 198, 200. The contacts 194, 196 and contact blades 198, 200 are retained on the bracket portion 202 of the assembly by binding post clamps 204. Conductor wires 208, 210 extend from the binding posts for the contacts 194, 196 for connection to a central control or computer for monitoring and/or detecting the condition, either up or down, of the ramp 

1. A vehicle switching arrangement comprising overhead monorail guideway means including means forming a first guideway section and means forming a second guideway section, said second guideway section diverging from said first guideway section and cooperating therewith to define a switch, a first guide blade on said first guideway section, a second guide blade on said second section and diverging from said first guide blade, a bogie having means for rollable support on said guideway means, said bogie including opposed guide wheels operably connected together for shifting between two modes, the guide wheels being on opposite sides of said first guide blade in either mode when the bogie is in said first section and approaching said second section, said guide blades having surface means engaged by said guide wheels and so shaped that one mode of said guide wheels will cause movement of said bogie through the switch and continue in said first section and the other mode of said guide wheels will cause movement of said bogie through said switch and onto said second section, and cooperating means on said bogie and guideway for shifting said guide wheels from one of the two modes to the other mode to control vehicle heading, including a ramp on said guideway and mechanism on said bogie operatively connected to said guide wheels and being actuated by said ramp, said ramp being movable from a first position in which said mechanism is unaffected by said ramp to a second position in which the ramp actuates the mechanism, said switching arrangement further including switch motor means having means for raising said ramp from said first position to said second position, means permitting lowering said ramp from said second position to said first position, and means for latching and unlatching the ramp in each of said positions.
 2. A switching arrangement according to claim 1 in which said guideway has side-by-side running surfaces and said bogie includes opposed load-supporting wheels respectively on said running surfaces, said switch forming a gap in one of said running surfaces whereby the load on one of the load-supporting wheels is removed and is added to the load of the other wheel when the bogie traverses the switch, said mechanism includes an arm having means engaging said ramp and operable to effect shifting of the guide wheels to the other mode upon movement to a predetermined position, and overtravel means permitting movement of said arm past said predetermined position as the bogie deflects upon removal of the load from said one wheel.
 3. A vehicle switching arrangement comprising overhead monorail guideway means including means forming a first guideway secton and means forming a second guideway section, said second guideway section diverging from said first guideway section and cooperating therewith to define a switch, guide blade means on said guideway sections, a bogie having means for rollable support on said guideway means, said bogie having guide wheels pantographically connected for relative movement between a first mode in which the guide wheels cooperate with the guide blade means for movement of the bogie through the switch in a direction that is a continuation of the first guideway section and a second mode in which the bogie is moved through the switch and onto said second guideway section, and guideway mounted ramp means for effecting movement of the guide wheels from one mode to the other mode, said guideway comprising running surface means, said bogie having load-supporting wheels for rollable support on said running surface means, said guide blade means comprising an upper guide blade above said running surface means and a lower guide blade below said running surface means, said guide wheels engaging said upper and lower guide blades on opposite sides of each guide blade as the bogie approaches said switch from said first section with the guide wheels in eiTher mode, and said guide wheels including upper guide wheels engaging one side of said upper guide blade when in one mode to effect guidance through said switch into said second section and engaging the other side of said upper guide blade when in the other mode to effect guidance through said switch and continued movement in said first section.
 4. In a monorail vehicle, a bogie having opposed load-supporting wheels for disposition on a monorail guideway, at least one pair of pantographically connected guide wheels, means for shifting said guide wheels relative to one another between two operating modes, means automatically forming a lock to maintain the guide wheels in the mode to which they have been shifted, and means operable to unlock the guide wheels prior to shifting to the opposite mode by said shifting means, said shifting means comprising a cam and an arm for actuating said cam, said lock means including a member relative to which said guide wheels are movable and said arm carrying a member for engagement with said relatively movable member to form said lock.
 5. In a monorail vehicle according to claim 4, said guide wheels being a pair of upper guide wheels and a pair of guide wheels pantographically connected together, the pantographs thus formed being linked together for joint movement.
 6. In a monorail vehicle according to claim 4, said guide wheels each being rotatable on respective brackets, pantograph graph links pivoted on said support and on said brackets, said cam being operable for lifting a bracket to effect said change of mode, and means permitting overtravel of said arm upon formation of said lock.
 7. The combination with a monorail guideway, a switching ramp pivotally mounted on said guideway, means for rotating the ramp to a switch-operating position and permitting return of the ramp to a non-operating position, and a vehicle on said guideway and having guide means for engaging the ramp in said switch-operating position to establish a predetermined vehicle guidance mode and cooperating with said guideway for controlling vehicle heading; said ramp rotating means comprising a switch motor that includes a power driven shaft, a driven structure including a ramp arm for lifting said ramp from said non-operating position to said switch-operating position, first means driving said driven structure from said power driven shaft, latching means responsive to the position of said driven structure and cooperating therewith for automatically latching said ramp in said switch-operating position when that position has been reached, and second means for unlatching said latching means to permit the ramp to move to its non-operating position.
 8. The combination according to claim 7 further including auxiliary locking means operable to retain said ramp in its non-operating position.
 9. The combination according to claim 7 in which said first and second means comprise first and second coaxial magnetic clutches and first and second eccentrics respectively driven through each clutch, and said driven structure comprises first and second follower means operated respectively by the eccentrics, said first follower means being movable to a position to cause engagement of said latch, and said second follower means being movable to release said latch.
 10. The combination according to claim 7 including means forming an electric circuit with said ramp therein in either said switch-operating position or said non-operating position whereby the position of the ramp can be electrically detected. 